[Swift-devel] Re: Swift Provenance

[Luiz M. R. Gadelha Jr.]

I agree that it's hard to make it generic. Initially, we are focusing on 
two users that will benefit from a simpler interface to the provenance 
database.

On 3/25/10 10:59 AM, Ben Clifford wrote:
>
> (cc swift devel in case others are interested)
>
>> We're going to work on making provenance more friendly to scientists, this
>> will involve writing stored procedures (or something equivalent) on top of the
>> provenance database to answer common questions that would be hard for a
>> scientist to express in SQL.
>
> ok.
>
> VDS1 had a provenance query language that had roughly the same goals (I
> think)
>
> I have some some criticisms of that:
>
> The language tried to support multiple database backend formats (XML and
> SQL) and in doing so failed to support either well (for example, sometimes
> it was desirable to make a join, but this was not supported meaning that
> you had to drop out to the SQL database directly for such queries). Pick
> one model and support it (I think SQL is my preferred one, but you may
> differ).
>
> Data was made available in a mishmash of models - for example, the
> abstract provenance query language would sometimes return an entire XML
> blob of data, which could not be further queried inside the provenance
> query language. This meant that having used to provenance query language
> to partly answer a question, in the end tools such as ad-hoc bad XML
> parsers written in perl ended up being used too (see the Provenance
> Challenge 1 queries for VDS for example). Make sure that whatever you
> produce can actually completely address the queries you are trying to
> address - if I have to hack some bodge on to the end of what you produce
> to answer my question, then I might as well have hit raw SQL in the first
> place.
>
> I'm not sure what the other people involved in OPM are up to now, but
> maybe they have interesting scientist-friendly approaches. OPM feels like
> a very good fit for Swift's provenance, and so there is some potential
> there if anyone else is actually working in the "easy query" space (not
> sure if anyone is).
>


-- 
Luiz M. R. Gadelha Jr.
http://www.lncc.br/~lgadelha